I'd like to see something like this using the NX protocol as the response time is much faster than VNC.
At my last few companies and my current one that I work out, one of the first things I do is setup an internal only Wiki server.
Not only does this let me document everything I can about the network but I also try an train my co-workers in using it to document information they feel is important for their job too.
The effectiveness though seems to be related to the level of computer literacy of the user, i.e. my last company the software developers went crazy with it and documented everything they could think of. But other than them or us in the I.T. dept, no one use would hardly touch it at all.
Either way it's still a simple method for your to store notes, diagrams or any information about your network in an easy to find single location that you feel would be important to the company should you leave for any reason.